This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A307080 #26 Jun 24 2019 20:09:50
%S A307080 1,0,-3,19,497,-1899,-489491,-15433676,618450881,120846851155,
%T A307080 7012261819901,-467816186167659,-175527285590430863,
%U A307080 -20961845760818684812,568194037748383908653,898095630359015975379151,220433074470274983356464897,16144974747716546214909454181
%N A307080 a(n) = exp(1) * Sum_{k>=0} (-1)^k*(n*k + 1)^n/k!.
%F A307080 a(n) = n! * [x^n] exp(1 + x - exp(n*x)).
%F A307080 a(n) = Sum_{k=0..n} binomial(n,k) * n^k * A000587(k).
%t A307080 Table[Exp[1] Sum[(-1)^k (n k + 1)^n/k!, {k, 0, Infinity}], {n, 0, 17}]
%t A307080 Table[n! SeriesCoefficient[Exp[1 + x - Exp[n x]], {x, 0, n}], {n, 0, 17}]
%t A307080 Join[{1}, Table[Sum[Binomial[n, k] n^k BellB[k, -1], {k, 0, n}], {n, 1, 17}]]
%Y A307080 Cf. A000587, A284860, A285065, A293037, A298373, A307066, A308645.
%K A307080 sign
%O A307080 0,3
%A A307080 _Ilya Gutkovskiy_, Jun 24 2019